haven't found similar bugreport here, so made a new post.
Crash report:
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Total Commander 7.50a fin
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Access violation at address 0069C378. Read of address 00000000.

Please report this error to the Author, with a description
of what you were doing when this error occurred!

Steps to reproduce:
1. enter any network folder accessible via SMB protocol (haven't tried to map it to any drive letter, just used e.g. "\\Diskstation\pictures\unsorted\") on left panel, and any subfolder for the same SMB share - for the right panel (e.g. "\\Diskstation\pictures\2007\") .
2. switch on thumbnail view for left panel. Setting "Loading thumbnails": tried "load from plugins", "Use explorer (OLE)" and "Use Irfan" - happens with any of these settings.
3. try to move some files from left panel to the right panel. in 80% i get crashes. if you need some more crash reports (i used Ctrl+C from that crash report window) - let me know.